Use iron-input bind-value in Polymer 2

Polymer 2 and Polymer 3 use bind-value with iron-input (see [1]).
Our code uses bind-value with input tag. It breaks tests with Polymer 2.
This problem doesn't affect end-users, because value is overriden on the
next open of the dialog.

References:
[1] https://www.webcomponents.org/element/@polymer/iron-input

Bug: Issue 10930
Change-Id: If1aa2be8a370810899f5aab5b14617f6e1580670
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js
index ece15bc..35b78ca 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js
+++ b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js
@@ -168,7 +168,11 @@
         // just make two separate queries.
         dialog.querySelectorAll('gr-autocomplete')
             .forEach(input => { input.text = ''; });
-        dialog.querySelectorAll('input')
+
+        // TODO: reveiw binding for input after drop Polymer 1 support
+        // All docs related to Polymer 2 set binding only for iron-input,
+        // and doesn't add binding to input.
+        dialog.querySelectorAll(window.POLYMER2 ? 'iron-input' : 'input')
             .forEach(input => { input.bindValue = ''; });
       }